Comparison of Basic Internal and External Egg Quality Traits of Brown and White Egg-laying Hens in Relationship to their Age

This study was focused on the comparison of the brown and white eggs from two laying hybrids. The objective was to assess basic quality traits of eggs from both groups of hens and compare them. The impact of how age influences the technological value of eggs was also observed. The most important correlations were calculated. Products of Czech original genetic programmes, Dominant Brown D 102 and Dominant Leghorn D 229 hens were included. A total of 1500 eggs were analysed. The egg collection was made for three consecutive days when the hens were at the 28, 35 and 59 weeks of age. The results showed that eggshell weight, yolk weight and yolk share increased with the age, while egg shape index, yolk index and albumen share decreased in both hybrids. Eggshell weight and share fluctuated with the age in both hybrids. Other traits differed within the hybrids. Interactions between age and hybrid were non-significant (P > 0.05) only in eggshell and yolk weight. The heaviest eggs were from 59-week-old Dominant Brown D 102 hens (68.89 g) and the lightest eggs were from 28-week-old Dominant Leghorn D 229 hens (57.76 g). Highly significant (P ≤ 0.001) positive correlations were found between egg weight and all individual egg components weights and between eggshell weight and yolk and albumen weight and eggshell thickness in both laying hybrids.